This project aims to advance understanding of brain processes in learning and memory by combined use of behavioral, neurochemical, neuropharmacological and neuroanatomical methods. Research is being pursued in three main directions; (a) We have found that giving formal training to rats in self-paced maze trials causes changes in brain chemistry and anatomy, as does experience in enriched environments, as we are defining these effects further. (B) Long-term storage of memory in mice is prevented by drugs that inhibit synthesis of protein or that impair transport of materials along branches of neurons, and we are using such agents to study steps that are required for formation of long-term memories. (c) We are investigating how brain lesions impair problem-solving behavior of rats and how post-lesion experience can help to overcome the deleterious effects of brain lesions. Effects of localized cortical lesions on the anatomy and biochemistry of other cortical regions are being studied. While post-lesion experience with varied inanimate stimuli aids subsequent problem-solving behavior, social experience has little or no beneficial effect.